[vsnet-grb-info 21820] GRB 190220B: Kitab Observatory optical upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23919
SUBJECT: GRB 190220B: Kitab Observatory optical upper limit
DATE:    19/02/21 14:58:34 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

S. Belkin (IKI), A. Novichonok (KIAM), A. Pozanenko (IKI), E. Mazaeva 
(IKI), A. Volnova (IKI), I. Molotov (KIAM) report on behalf of larger 
GRB follow-up collaboration:

We observed the field of INTEGRAL GRB 190220B (Gotz et al., GCN  23915) 
  with RC-36 0.36-m telescope of Kitab Observatory starting on Feb. 20 
(UT) 23:20:25 in  Clear filter.   We do not find any optical afterglow 
candidate in the INTEGRAL  GRB 190220B localization error circle (Gotz, 
et al., GCN  23915) with is in agreement with earlier non detection by 
BOOTES-4 (Hu et al., GCN  23916). Preliminary photometry of the field is 
following.

Date       UT start   t-T0       Filter Exp.    OT     Err.   UL(3sigma)
                       (mid, days)        (s)

2019-02-20 23:20:25   0.14972    CR     48*60   19.0   n/d    n/d

The photometry is based on the nearby USNO-B1 (R2) stars.
  .